Taylor Swift broke her usual political silence on Sunday to endorse two Democratic candidates in her home state of Tennessee on Instagram.

Vote.org, an organization dedicated to increasing voter registration, said it saw 65,000 people register using its online tool in the 24 hours after Swift's post.

Vote.org said that in Tennessee, 2,144 people registered in the 36 hours after Swift's post, more than double the number of people who did so in August.

Swift denounced the Republican US Senate candidate Marsha Blackburn in her post, writing: "I cannot vote for someone who will not be willing to fight for dignity for ALL Americans, no matter their skin color, gender or who they love."

About 65,000 people nationwide registered to vote in the 24 hours since Taylor Swift broke her usual political silence in an Instagram post on Sunday to endorse two Democratic candidates in Tennessee, according to Vote.org.

The voter-registration organization said 56,669 people used its online tool to register to vote in August and 190,178 did in September. (The higher figure was due to National Voter Registration Day on September 25, it said.)

Vote.org said on Tuesday that 44,801 people who used its tool to register to vote since Swift's post were between the ages of 18 and 24.

"We're especially happy to see that because we know voting is habit-forming," Vote.org said in a statement to Business Insider. "Statistically, a young person who votes in 2018 is 55% more likely to vote again in 2020."

In Tennessee, Swift's home state, 2,144 people registered on Vote.org in the 36 hours after Swift's post, more than double the number of people who did so in August.

The organization tracks the number of people who use its tools so it can follow up and make sure they vote, Vote.org COO Raven Brooks told Business Insider.

Vote.org said more people had registered so far in October than in any other month except September. Just 12,846 people registered in January and 14,599 did in March.

In her Instagram post on Sunday evening, Swift acknowledged her usual reluctance to publicly express political opinions but said she was speaking now following "several events in my life and in the world in the past two years."

Swift encouraged her 112 million followers to register, directing them to the Vote.org website.

"October 9th is the LAST DAY to register to vote in the state of TN," she said in the post. "Go to vote.org and you can find all the info. Happy Voting!"

In her post, Swift expressed support for gender and racial equality and equal rights for LGBTQ people, and she denounced Republican Rep. Marsha Blackburn, who is running for a US Senate seat in Tennessee. Blackburn has opposed same-sex marriage and argued in favor of defunding Planned Parenthood.

"I cannot vote for someone who will not be willing to fight for dignity for ALL Americans, no matter their skin color, gender or who they love," Swift wrote.

Swift denounced Marsha Blackburn, the Republican US Senate candidate who spoke at a campaign rally for President Donald Trump in Tennessee on October 1. Sean Rayford/Getty Images

Swift endorsed Phil Bredesen, the former Tennessee governor running against Blackburn, and Rep. Jim Cooper, who's running for reelection in Tennessee's 5th District, which includes Nashville.

"I always have and always will cast my vote based on which candidate will protect and fight for the human rights I believe we all deserve in this country," Swift wrote.

"I believe in the fight for LGBTQ rights, and that any form of discrimination based on sexual orientation or gender is WRONG. I believe that the systemic racism we still see in this country towards people of color is terrifying, sickening and prevalent."

Swift's post angered some conservatives and members of the so-called alt-right. President Donald Trump said on Monday that he liked Swift's music "about 25% less" since she endorsed the two Democrats.